Theranostics 2020; 10(14):6372-6383. doi:10.7150/thno.46833

Research Paper

Risk factors for adverse clinical outcomes with COVID-19 in China: a multicenter, retrospective, observational study

Peng Peng Xu1#, Rong Hua Tian2#, Song Luo1#, Zi Yue Zu1#, Bin Fan3#, Xi Ming Wang4, Kai Xu5,6, Jiang Tao Wang7, Juan Zhu8, Ji Chan Shi9, Feng Chen10, Bing Wan11, Zhi Han Yan12, Rong Pin Wang13, Wen Chen14, Wen Hui Fan15, Can Zhang16, Meng Jie Lu1, Zhi Yuan Sun1, Chang Sheng Zhou1, Li Na Zhang17, Fei Xia1, Li Qi1, Wei Zhang1, Jing Zhong1, Xiao Xue Liu1, Qi Rui Zhang1, Guang Ming Lu1✉, Long Jiang Zhang1✉

1. Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210002, China.
2. Department of Medical Imaging, Xiaogan Central Hospital of Wuhan University of Science and Technology, Xiaogan, Hubei, China.
3. Huanggang Central Hospital, No. 11, Kaopeng Road, Huangzhou District, Huanggang, Hubei, China.
4. Department of Medical Imaging, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China.
5. Department of Radiology, the Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China.
6. Institute of Medical Imaging and Digital Medicine, Xuzhou Medical University, Xuzhou, Jiangsu, China.
7. Department of Radiology, Xiangyang Central Hospital, Affiliated Hospital of Hubei University of Arts and Science, Xiangyang, Hubei, China.
8. Department of Medical Imaging, the Affiliated Anqing Hospital of Anhui Medical University, Anqing, Anhui, China.
9. Departments of Infectious Disease & Department of Medical Imaging, Wenzhou Central Hospital, Wenzhou, Zhejiang, China.
10. Department of Radiology, Hainan General Hospital, Haikou, Hainan, China.
11. Department of Medical Imaging, Jingzhou Central Hospital, The Second Clinical Medical College, Yangtze University, Jingzhou, Hubei, China.
12. Department of Medical Imaging, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, PR China.
13. Department of Medical Imaging, Guizhou Provincial People's Hospital, Guiyang, China.
14. Department of Medical Imaging, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei, China.
15. Department of Radiology, General Hospital of the Yangtze River Shipping, Wuhan, Hubei, China.
16. Department of Radiology, Yichang Central People's Hospital, Yichang, Hubei, China.
17. Department of Radiology, The First Hospital of China Medical University, Shenyang, Liaoning, China.
#These authors contributed equally to this work.

This is an open access article distributed under the terms of the Creative Commons Attribution License ( See for full terms and conditions.
Xu PP, Tian RH, Luo S, Zu ZY, Fan B, Wang XM, Xu K, Wang JT, Zhu J, Shi JC, Chen F, Wan B, Yan ZH, Wang RP, Chen W, Fan WH, Zhang C, Lu MJ, Sun ZY, Zhou CS, Zhang LN, Xia F, Qi L, Zhang W, Zhong J, Liu XX, Zhang QR, Lu GM, Zhang LJ. Risk factors for adverse clinical outcomes with COVID-19 in China: a multicenter, retrospective, observational study. Theranostics 2020; 10(14):6372-6383. doi:10.7150/thno.46833. Available from

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Background: The risk factors for adverse events of Coronavirus Disease-19 (COVID-19) have not been well described. We aimed to explore the predictive value of clinical, laboratory and CT imaging characteristics on admission for short-term outcomes of COVID-19 patients.

Methods: This multicenter, retrospective, observation study enrolled 703 laboratory-confirmed COVID-19 patients admitted to 16 tertiary hospitals from 8 provinces in China between January 10, 2020 and March 13, 2020. Demographic, clinical, laboratory data, CT imaging findings on admission and clinical outcomes were collected and compared. The primary endpoint was in-hospital death, the secondary endpoints were composite clinical adverse outcomes including in-hospital death, admission to intensive care unit (ICU) and requiring invasive mechanical ventilation support (IMV). Multivariable Cox regression, Kaplan-Meier plots and log-rank test were used to explore risk factors related to in-hospital death and in-hospital adverse outcomes.

Results: Of 703 patients, 55 (8%) developed adverse outcomes (including 33 deceased), 648 (92%) discharged without any adverse outcome. Multivariable regression analysis showed risk factors associated with in-hospital death included ≥ 2 comorbidities (hazard ratio [HR], 6.734; 95% CI; 3.239-14.003, p < 0.001), leukocytosis (HR, 9.639; 95% CI, 4.572-20.321, p < 0.001), lymphopenia (HR, 4.579; 95% CI, 1.334-15.715, p = 0.016) and CT severity score > 14 (HR, 2.915; 95% CI, 1.376-6.177, p = 0.005) on admission, while older age (HR, 2.231; 95% CI, 1.124-4.427, p = 0.022), ≥ 2 comorbidities (HR, 4.778; 95% CI; 2.451-9.315, p < 0.001), leukocytosis (HR, 6.349; 95% CI; 3.330-12.108, p < 0.001), lymphopenia (HR, 3.014; 95% CI; 1.356-6.697, p = 0.007) and CT severity score > 14 (HR, 1.946; 95% CI; 1.095-3.459, p = 0.023) were associated with increased odds of composite adverse outcomes.

Conclusion: The risk factors of older age, multiple comorbidities, leukocytosis, lymphopenia and higher CT severity score could help clinicians identify patients with potential adverse events.

Keywords: COVID-19, Coronavirus, Pneumonia, Risk factor, Mortality